In this study, the electrochemical behavior and properties of the novel LiFePO4-based composite cathode material with a water-soluble binder LA-133 and a conductive polymer PEDOT:PSS (poly-3,4-ethylenedioxythiophene: polystyrenesulfonate) as an aqueous dispersion were studied. Using the conductive polymer in combination with a water-soluble binder LA-133 allows to reduce the proportion of electrochemically inactive components (up to 10\%) and thus to increase its specific capacity for a given weight of the active material.